Binding string variable to WPF, data leak?

Binding string variable to WPF, data leak?

Hi,
I created a simple XAML file containing not much more than a label and a viewbox. When I try to bind the value of a string variable to the label's content, the runtime will crash.
Numerical values work fine though. The variable is provided via S7 TCP/IP driver.
As a work around I created an internal string variable, and binding works as expexted. But, the runtime leaks memory ~20MByte causing it to freez after a while.
Runtime is Zenon 6.51SP0, Windows XP, .Net3.5
Any help appriciated :)

This is a migrated post! Originally posted on 25.01.2013 by user sebastian.lenk. Please be aware that information can be outdated.